Electric horn



Mamh 21, 1950 i w, RHQDES 2,501,234

ELECTRIC HORN Filed April 10, 1948 INVENTOR. MZZzam Z filaa e.

TOP/V575.

Patented Mar. 21, 1950 William E. Rhodes, Marion, ln'dc, assignor to Delta Electric Company, Marion, Inch-,- 3; corporation of Indiana Application April 10, 1948, Serial N0.- 2022? This invention relates to warning devices generally and more particularly to electromagnetically operable horns adapted for emitting sound blasts of a controllable duration.

Warning devices of this general character which vibrate a diaphragm by an electromagnetica-lly actuated striker have heretofore utilized circuit interrupter mechanisms which were separate and distinct from the striker and diaphragm elements, and, therefore, required various adjusting expedients in order tosecure the'proper operation thereof.

The present invention contemplates the provision of a new and novel electrical horn in which the separate circuit interrupter mechanism has been eliminated andin its stead, the diaphragm and striking element made parts of the interrupter mechanism, thereby eliminating the: ad.- justing expedients heretofore required.

An object of the present invention therefore is to provide a novel electrical warning device in the form of a sound-emitting horn.

Another object of the invention is to provide a novel sound-emitting horn which is simple: in construction and which possesses but aminimum number of parts.

A further object is to provide an electrical horn embodying a novel circuit interrupting mechanism therein.

Another object is to provide a novel electrical horn in which the adjustment mechanism here-- tofore required for setting of the circuit interrupter elements relative to the striker or armature for proper operation, has been eliminated.

Another and still further object of the present invention is to provide a novel electrical horn in which the circuit making or breaking elements are carried directly by the diaphragm and striker elements.

Other objects and advantages of the present invention will become apparent from the following specification, the accompanying drawing and the appended claim.

In the drawing, wherein like reference characters refer to like parts throughout the several views;

Figure 1 is a rear elevation view of the novel horn of the present invention;

Fig. 2 is a side elevation view in section taken substantially along line 2-2 of Fig. 1; and

Fig. 3 is a sectional view taken substantially along line 35-41 of Fig. 2.

Referring now to the drawings for a more detailed description of the present invention and more particularly to Fig. 2 thereof, the novel 1- Claim. (CL 177 7 2.. electrical horn hereof is'shown as comprising a rear cylindrical casing I'll having an outwardly extending flange H- at the open end thereof to which is secured an intem'iediate casing l2 by way of suitable means'such as rivets 13 (Fig. 1), for example. Intermediate casing I2 is, in turn, likewise providedat its open end with an outwardly extending flange 14 to which is secured an end casing. I5 by way of clips I6 secured to and formed integrally with casing l5.

Prior to thetime that clips l6 are caused to engage with flange t4- oft'he intermediate casing to secure the end. casing to casing l2, a diaphragm H of thin resilient material is brought into contact with the outer surface of flange M or casing 12 so that when thec'lip's are caused to engage flange t4; the diaphragm is securely clampedand supported between casings l2 and 15.

The end wall of rear casing [0' supports an iron core [8" thereon, the wall to this end being apertur'ed' to rest on a shoulder I9 of the core. The core, moreover, has a decreased portion which extends slightly beyond the end wall and Whichis flanged over as shown at 20 (Fig. 2) to clamp the end wall to shoulder [9. If desired, for mounting purposes, a threaded bore 2| may be provided in core [8;

The outer surface of core [8' supports a substantially annular cylindrical member 22 there- On which is flanged at both ends to receive end disks 23 and 24 which support between their outer ends, an annular shell 25. The end disks 23, 24, together with member 22 and shell 25, define a chamber for accommodating therein an electrical coil 26 consisting of any desired number of turns of Wire.

The end wall of intermediate casing I2 is provided with an opening 21 for accommodating an armature or striker member 28 therein for motion transversely thereof. Armature 28 has a reduced end 29 at which point it is securely fastened to the central portion of a pre-loaded spring member 30 which is suitably apertured to receive this end. A washer 3| is fitted over the reduced end 29 and the end 29 is riveted over the washer to hold it in place. Thus the washer maintains the spring and armature in an assembled condition.

The outer ends of spring 30 are provided with apertures 3| and 32 (Fig. 3) through which pass rivets 33 and 34 whereby spring 36 is secured to diaphragm IT in a substantially spaced parallel relation thereto. Interposed between the diaphragm and the spring are insulated spacers or supports 35 and 36 while insulation washers 31 3 and 38 are interposed between the heads of rivets 33, 34 and the diaphragm for a purpose presently to appear.

Coming now to the novel arrangement of the present invention whereby the conventional circuit interrupting mechanism heretofore known has been eliminated, the reduced end 29 of armature 28 has suitably fastened thereto, a contact element 39 which is adapted for cooperation with a second contact element 40 fastened in any desired manner at the center of the diaphragm I7 opposite contact 39. Inasmuch as contact element 39 is carried by armature 28 it not only functions as a part of the circuit interrupter mechanism but also functions as part of the striking element which imparts vibration to diaphragm I! by intermittent engagement therewith.

Current for energizing coil 26 is conducted thereto from a suitable battery (not shown) by way of a conductor 4| connected to one end of the coil, the opposite end of which is grounded to casing 12 by way of a conductor 42 (Fig. 2) which connects with a terminal 43 held in place by a rivet 33, spring 30, contacts 39 and 40, and diaphragm I! which is in contact with flange I4 of casing I2. The horn case defined by casings l0, I2 and i5 may be connected with the opposite side of the battery through a conventional switch (not shown).

With the parts at rest as shown in Fig. 2, when the switch is closed, the circuit is completed whereupon coil 26 is energized to develop a local magnetic field thereabout. As a result of the locally generated magnetic field, armature 28 is attracted to core l8 thereby disengaging contact 39 from contact 40 whereby the circuit is momentarily broken causing de-energization of coil 26 and the consequent collapse of the magnetic field previously developed thereby. Spring 36 thereupon draws armature 28 to the left, as viewed in Fig. 2, to reestablish engagement between contacts 39 and 40 and to thus close the circuit to re-energize coil 26. In this manner an oscillatory motion on the part of armature 28 is generated, the armature striking the diaphragm each time as it moves to the left of coil 26 to impart a vibratory motion to the diaphragm at an audible frequency. The sound thus generated is emitted from end casing through an opening 44 formed at a central portion of the casing for this purpose.

There has thus been provided a novel electrical horn of the vibratory type in which the ad-- justing expedients heretofore required to start and maintain continued operation of the horn have been eliminated. This objective has been attained by the pre-loaded spring 30 and its manner of assembly with diaphragm H. The frequency of the horn tone is determined by the weight and the position of armature 28, the thickness of spring 30, as well as the thickness of diaphragm IT. The horn, therefore, as will now be apparent, may be operated as desired by making a connection between coil 26 with the source of direct current supply.

While one form of the invention is shown and described herein, it is apparent that others are available within the spirit of the invention and within the scope of the appended claim.

What is claimed is:

An electric horn comprising a casing of electrically conducting material, a flexible metal diaphragm adapted to vibrate at audible frequency arranged transversely of said casing and electrically connected thereto, a metal leaf spring behind and parallel to said diaphragm, connectors fastening the ends of said leaf spring to the diaphragm, means electrically insulating the fastened ends of the leaf spring from said diaphragm, a solenoid in the casing behind said leaf spring including a coil and an armature, said coil being electrically connected at one end to a fastened end of said leaf spring and said armature being connected to said spring substantially midway between the ends of the latter, and mutually engageable and disengageable electric contacts carried by said armature and said diaphragm.

WILLIAM E. RHODES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 986,707 Goldstein Mar. 14, 1911 2,338,640 Hellier Jan. 4, 1944 

